CNN:

Cockroaches have a memory and can be taught to salivate in response to neutral stimuli in the way that Pavlov’s dogs would do when the famed Russian doctor rang his bell, Japanese researchers say.

Such "conditioning" can only take place when there is memory and learning, and this salivating response had only previously been proven in humans and dogs.

Now, cockroaches appear to have that aptitude too.

Ya know, I could have gone my whole life without having the image of clever drooling cockroaches.  Thanks, CNN.